


Golden-Tinged Hoarfrost

by May_Ravenstaff, Twice_Infinity_Three_Of_Zero



Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: AU, Alternate Universe - Canon Divergence, Alternate Universe - Cyberpunk, Bymitri, Cyberpunk, Everyone Is Gay, F/F, Female My Unit | Byleth, How Do I Tag, I Wrote This Instead of Sleeping, Kind of Canon Compliant, M/M, Male My Unit | Byleth, Modern Cyberpunk, Mostly canon divergent, Other Additional Tags to Be Added, Tags May Change, Twin Byleth AU, Twinleth, cathmir, cool weapons, dimileth
Language: English
Status: In-Progress
Published: 2020-10-26
Updated: 2020-12-15
Packaged: 2021-03-07 16:09:10
Rating: Teen And Up Audiences
Warnings: Creator Chose Not To Use Archive Warnings, Graphic Depictions Of Violence
Chapters: 2
Words: 4,233
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26680429
Author URL: https://archiveofourown.org/users/May_Ravenstaff/pseuds/May_Ravenstaff, https://archiveofourown.org/users/Twice_Infinity_Three_Of_Zero/pseuds/Twice_Infinity_Three_Of_Zero
Summary: The twins don't know the real reason they were invited to fight for the church; and the students who were forced into the life of church service intend to help them find out.And they better figure out the reason quick. After all, it's dangerous on the streets without a gang at your back.OrThe city of Fódlan and it's districts have fallen to ruin under the conspiracy of the Seiros Knights; a religious group of rebels attempting to overthrow the current empire and bring everlasting peace to the three city boroughs.Enter two young mercenary twins, both naïve enough to fall for the concept of citywide peace. Maybe the truth will reveal itself in time...
Relationships: Catherine/Shamir Nevrand, Dimitri Alexandre Blaiddyd/My Unit | Byleth
Comments: 7
Kudos: 17





	1. The Bar, the Blond, and the unbearable sirens

**Author's Note:**

> Jess and I finally wrote a story together! I knew this would be fun, and I was completely right. Now, the only thing I have left to say is an excerpt from our conversations.
> 
> FIN: whatever we write together will be AMAZING.
> 
> JESS: damn right it will! XD

**Notes for the Chapter:**

> FIN: Believe me, whatever we write together will be AMAZING.
> 
> JESS: damn right it will!

The city was quiet.

Well, it was as quiet as a neo-city could get, the strips of neon flashing and producing wet strips of brilliant color on the stone streets. The city of Remire was dark, dirty, and relatively small, by all city standards in this modern age. A thick layer of smog and heavy thunderstorm clouds covered the once beautiful twilight sky, producing rain and lightning that stung every time it hit skin.

Three figures approached an alleyway, void of sound technology and as dirty (if not dirtier) than the rest of the streets themselves.

These figures wore mercenaries’ armor. The soft glow of the seams illuminating the plates ever so softly gave the figures and ethereal aura. The first figure, carrying a techie lance, stood at the front of a triangle, the other two hanging back and staying close to one another. They carried blue, glowing swords, sheathed carefully at their waists.

The trio reached a steel plated door, haphazardly constructed with loose screws and bolts. The neon sign above was in an illegible font, colors pulsing with the advertising technology this place could barely afford.

The tallest shadow (the first) knock three times on the steel door, and the eyeslat on the steel slid open, revealing one yellow eye and one bionic, electric blue one.

“Whaddya want?” the voice below the eyes said, cautiously.

The first figure replied. “A drink.”

“Who is this?”

“Jeralt Eisner and his twins.”

The eyeslat slid shut again, and the door fully opened this time. “C’mon in, but don’t go makin’ any trouble, ya’hear?”

Jeralt stepped in the bar without hesitation, removing his hood and exposing his ears to the lively sound of the bar inside. His “twins” were not so readily trusting. They hung behind, clutching one another’s arms. The taller of the twins removed his hood.

He was a sight to behold, with ash blue hair and shining eyes. He had an expression like stone, and his left arm was a gorgeously made electric prosthetic. His human hand grabbed his twin’s left.

She was just as exquisite, very much like her brother appearance-wise. Long blue locks flowed around her shoulders and her robotic right arm rested carefully on the hilt of her sword. She grasped her brother’s hand carefully.

They were about to step inside the open door, when a strange sound caught both of their ears.

It was the sound of a poorly made bionic leg clunking haphazardly down the wet stone steps.

They turned to the sound, and their eyes revealed a boy of about seventeen. He had short, blonde hair; ice blue eyes and an expression of pure pain and fear. His pant leg ripped at the thigh, revealing a broken, rusted leg falling apart at the plates. He limped on it, making grunts and small noises of absolute exhaustion. He clutched a glowing lance and leaned on it like a crutch.

"Dammit," cursed the man who had just let the three of them into the bar. "Kid, I told you this wasn't some safehouse for you and your goons."

Folks around the room tittered nervously as the blonde boy--more a man than child--looked up at the person who spoke. He growled and it sounded rusty, like the augments in his throat were in need of attention. In fact, most of his cybernetics needed care. Even his arms, which worked better than his leg, sparked in places with frayed cables exposed.

"Take it up with Rhea," he said. And with that, he hobbled over to a table, resting his lance against it as he stumbled into a seat. 

Jeralt's hands were at their backs, guiding them away from the man who'd entered. "Remember, we're not here for trouble," whispered their father. 

"He's hurt," B said, looking over his shoulder. The blond had taken his leg off and was swearing up a storm as he tried to repair it, clearly struggling.

By picked at her mechanical arm as Jeralt explained why it was a bad idea to associate with the half dead man who walked in. At one point, her arm had been covered with skin. But that had been ages ago. Now flecks of dried silicone, carbon, whatever it was, clung at the joints of her elbow and wrist. In some ways, she didn't seem much different than the bar's newest occupant.

B's eye twitched; one of his tics that gave away the emotion that never showed on his face. B was the mechanic in the family, showing adept skills toward technology since a young age. He had built both his and his sister's mechanical limbs nearly effortlessly.

Jeralt swore softly as his bad knee bent to place his belongings on a table. He eyed the bartender, trying to pick up the conversation they were engaged in with a nearby bounty hunter.

By sighed resignedly. She reached into her pocket and pulled out a smooshed paper package, withdrawing a cigarette from it. Even as technology advanced so rapidly, some classics never went out of style. By snapped her fingers next to the end of it and the sparks from metal grinding against metal lit the tobacco. She breathed in.

"Ah," she sighed, content.

B gave her a look as he pulled a chair out next to his sister, and popped open a compartment in his arm. He withdrew a circuit and a small tool, and reset wires into their respective places.

"By," B began, softly in the accented voice she knew so well. "I told you that smoking might just fry your circuit, and believe me, I'm not looking forward to having to open your ribcage again." The lilt to his voice caught softly on his tongue as he picked at the circuit board in front of him. By scoffed.

"Goddess help me," Jeralt muttered, looking from one of his kids to the other. "You keep an eye on each other. I'm gonna talk to the owner. Gonna see if he has work for us."

"Good luck," By said, content to smoke. B nodded in silent agreement. She drew a long breath from her cigarette. Her lungs had been fucked up in a fire some time ago and been replaced with cybernetics. They'd had more money then. 

Loud sirens began to scream outside. There wasn't an eye that didn't look towards the wounded man and now her brother too. The sirens didn't seem to be getting closer, but weren't going away. Trouble, but not immediate.

Maybe she'd get a chance to finish her cig before things went crazy.

By stared at her brother as she puffed on her cigarette, smoke like an ashen halo around her skull.

He was working diligently, his nose inches from his work as he squinted his eyes in a way that was almost endearing. She was the older of the twins, and much as she might deny it, she loved her little brother. He was her second half, and she his.

By and B might’ve shared the same name, yet they were like two sides of the same coin.

B was the taller one, but he was lighter on his feet and sharp in his senses. He could hear from a ridiculous distance, and could dance around every attack that was thrown his way. But what he made up for in grace, he lacked in strength. Sure, he was more than capable of lifting his own body weight and possibly a cannon twice his size, but his swing compared like nothing to his sisters’.

By was shorter, but she was the heavy hitter. Bounty hunters wept at the mercy of her sword. One swing of the blade could down several men twice her size. Yet while she welded immense power, she was severely missing dexterity herself. She was often disappointed in herself when she tripped over her steel boots, or took a hit her brother could easily have dodged.

Their emotional attachment to one another was both a blessing and a curse; on the battlefield one twin made up for what the other lacked. Together, they were the Ashen Demons- surviving the company of the Byleth twins was near unheard of. But in the city they couldn’t stay apart. Stubborn and lax By might be, but she could often be found rubbing small circles of comfort on her brother’s back. Self-involved and reclusive B was, he couldn’t bear to leave his sister’s company.

By’s eyes snapped back to the icy glare of B’s as she woke from her stupor. She breathed in the tobacco of her cigarette as she noticed B looking straight at her.

“Did you say my name?” Her mountain accent wasn’t as clear as B’s, but it was definitely there.

He hung his head, which By knew to take as a bad sign. “Yes,” he said, softly.

She scoffed inwardly; B was never one to elaborate by himself, and By always had to push.

“What didja want?”

“The sirens are getting louder, and I can hear yelling,” he said.

Of course, she heard no such thing, but her trust in her brother’s senses was as full as it could be.

“Trouble?” She asked.

He shrugged, and finished his work quietly. The circuit was placed neatly into the mechanical forearm, and B tested his work.

“Possibly.”

The door burst open, as if kicked, and both By and B bolted upright. Two figures were pressed against the door, holding it shut as they breathed heavily.

The sirens blared; the figure with dark hair and skin winced inwardly as he gingerly touched a burn through his armor. He was clad in gold metal, his elbows and knees made of steel and wires as they held together human limbs. His hair was ruffled and a dark brown, skin golden- possibly a southerner.

The second figure was short, sporting long white hair and purple eyes, obviously bionic. They swiveled in their sockets, taking in the scene around her. She wore metallic red, her left leg bolts and plates.

The barkeep snarled. “Dammit, I told ya I don’t want any fuckin’ Seiros kids in ‘ere!”

The neon lights lighting up the bar flickered and sent a shower of sparks over a group of ladies in the corner. They shrieked, and the tall figure at the door caught eyes with the blond man at the table, wide eyed and clutching a pair of pliers.

“Dimitri!”

The blond winced, his icy eyes running over the two at the door. But, if things weren’t strange enough, he sank into a low bow.

“Claude. Edelgard. May I ask what the hell happened to you?”

Claude touched the burn on his side again, and Edelgard flexed her mechanical knee, keeping her electric purple eyes trained on Dimitri. She piped up softly.

“We were attacked!”

"Looks like you were too," Claude said, giving Dimitri a once over. 

Dimitir, surprisingly, grinned. "They gave me a good run, but I put them in a ditch. You shake yours?"

Edelgard shook her head. "Too many. They had an ambush set up."

"Got a few, but they were too dug in the break through. Maybe they were Kostas', not sure." Claude sat down next to Dimitri and stole his drink, finishing it. The way Dimitri didn't even blink told that it was standard affair.

B kept working at her arm, almost lost to the world. Almost. He had an eye on the frankly colorful trio.

By wore a lazy smirk, watching them. She smelled work.

"Is the business sector clear?" Dimitri asked.

Edelgard shook her head. "Doubt it. Haven't heard from Dedue and Hubert. They were supposed to clear it."

Claude raised a hand to his ear and cocked his head for a moment. "Hilda says that Security has narrowed us down to this sector. They're beginning a sweep. Whatever plan you two have, we better get on it."

"Aren't plans your forte," Edelgard shot back.

"Only when they require a degree of stealth. A scheme where we charge out, guns blazing? That's more your two's area."

"He's not wrong," Dimitri chuckled. "We can take them."

"Bullshit, your legs are fucked." Edelgard crossed her arms. "And we couldn't take all of RS even fully functional." Remire Security, dogs to the corporations. There wasn't a soul in the city that expected justice to come from their hands. Just punishment.

"Then perhaps we've got time to bask in our good fortune." Claude winked at him companions, turning to the twins. "You there, mechanic!"

B stiffened. By shifted herself protectively in front of him. "What do you want?" she asked.

"Just a bit of help for a few vigilantes. I assure you it's entirely exotic and exciting and any other adjective with an E," Claude said.

"We are broke," B whispered helpfully. By nodded.

"I'm sure we can assist, for a price," she said.

"Wonderful!" Claude clapped. "Come, sit with us."

By stood up first, walking over. B went and sat down next to Dimitri while she remained standing.

"One rule, my brother doesn't get harmed by this RS business." By's eyes were hard.

Edelgard nodded. "Trust me, we plan not to get tangled with them more. If we can get repaired enough to slip out the back, we will."

By nodded and sat. 

B grabbed his sister’s fingers and gave them a reassuring squeeze, an uneasy emotion flowering through his head. No one has ever requested his services before; let alone this obviously noble man who walked into a commoner’s bar with his blue silk cape and pin. They were staring at him expectantly, and B felt a bitter taste on his tongue. 

“I’ll set to work, then,” he said, softly as he pressed a small button on his robotic bicep. 

He was a walking toolbox; his arm transformed into a set of compartments, each housing copper wires, unfinished circuits and pliers and wrenches galore. B was never unprepared. 

He sat heavily next to the blond man in the chair, who gave him a small, confident smile. B didn’t reply, but instead gestured to his poorly wired leg. 

“...may I?” 

“Of course.” 

Dimitri sat back on his chair so that his leg rested on the table, and instantly B moved his magnifying visor over his eye. The sound of the mechanism clicking into place and the soft whirring of the visor scanning the adaptation in front of him was reassuring to his ears. The pointer finger of his mechanical arm morphed into a small melding laser. 

Without another word, B set to work, melding and plying and wrenching the bolts so they sat tight against Dimitri’s skin. He knew he was timed, with the sirens outside getting gradually more incessant in volume. The plates were replaced, the wires tied and the sparking gears oiled and reset. Within two minutes he was finished, putting the last bolt in place. 

Instantly B got up and stepped back, to be level with his sister. His visor glowed through the blueness of his eye, and he wore an expressionless face. 

By grabbed his wrist and their fingers intertwined as Dimitri stretched and flexed his leg. 

“Good job,” she whispered. A complement from By to a stranger was almost unheard of, but this was her brother; her other half. 

B smiled. 

Dimitri hopped to his feet, stretching the mechanism and hearing the hinge slide smoothly. He turned to Claude and Edelgard, and opened his mouth to speak- 

But was interrupted as the door to the pub slammed open. 

A ferocious looking man emerged, scars coating his face and old furs covering an entirely human body. He scanned the bar as they all went silent, and he cocked the ancient revolver he held in his left hand. 

“I fooouunndd youuu,” he said, in a raspy, singsong voice. “Kostas will be pleased. Noble brats set a high price; and especially the Seiros ones.” The revolver smoked from its last shot; it had been fired, and very recently. 

B couldn’t help but wonder who its last victim was. 

He lowered his eyes to the floor as the bandit spat on the ground. What B did do, however, was reach a stealthy hand into his back pocket, and remove two small earpieces. 

He dug the piece into his right ear, and moved a hand around his sister’s torso- his hand placed the earpiece in hers. 

By understood, and dug the piece into her ear, which prompted B to click a small button on his arm. 

Music flooded his ear. 

It opened with a steady drum and bass line, the tell-tale mark of the song B and By could listen to for hours. 

By smiled as she heard the song open, and she shot a grin at B. 

“Good choice!” 

Instantly By’s techie arm shifted into the pulse cannon B had spent so many hours designing. The plates moved on smooth oil, shifting silently as the gears reworked themselves to fit amongst the wires. She raised her arm, and in one loud shot, a pulse ring exploded from the cannon and flew into the man’s chest. 

The synthesizer and voice melody rose from the beat as the backfire from By’s pulse cannon wrenched her shoulder, but it wasn’t anything she wasn’t used to. The man stood, stunned as he crumpled to the ground in a heap. 

By smiled and stared at the smoke filing from the cannon that replaced her arm. B tensed, and his plated arm shifted into a giant knife; the blade replaced by a contained laser, enough power to easily cut a diamond in half. The music blasted through their skulls, familiar lyrics pulsing to the beat. 

Dimitri, Claude and Edelgard stood in horror as By easily disposed of the bandit, and B assumed a ready stance protectively over his sister as her cannon recharged. 

They knew what was coming. 

The door exploded off its hinges, and around twelve more men stampeded into the bar, guns raised and eyes wild. 

The music pounded through B’s ears as he glanced at his sister. She wore a grin, and the soft ‘clunk’ of her cannon recharge was reassuring to the ears. 

She looked each and every bandit in the eyes, and moved her arm over B’s torso as she spoke in a snarl. 

“Come get us.”


	2. Random (And Expensive) Farewells

**Notes for the Chapter:**

> Jess: We need to be on our comedy game for these messages.
> 
> Fin: OUR KUDOS DEPEND ON IT

B stepped forward, his boot slamming against cold stone as his sister did the same a few places ahead of him. The music pounded in their skulls as By looked back and sent a curt nod at B. He nodded back.

They charged.

The bandits on the other side of the bar met them halfway- they were outnumbered, ten to one. Jeralt was herding screaming citizens out the back door- there was no possible way they'd get his help anytime soon.

B's knife-hand sliced through cold air, bringing it down on the neck of a bandit. By did the same, her heavy sword cutting through them like jell-o.

B's mind hit a wall- these mercenaries were horribly trained. No one had even thought to give them proper lessons; their stances were wide open, their swings wild.

By obviously felt the same, her face revealed a confused sort of expression. But if it were anyone else looking at her, she would've shown nothing but indifference.

As the twins cut down several more bandits, B's eye caught flashes of red, yellow, and blue. The three kid had entered the brawl- Edelgard with a wavering blue axe, Dmitri with a sharp glowing lance and Claude with a bow- held together by a neon string.

Dimitri let out a war cry as his lance sparred three bandits, relegated smashed on into the ground. Claude sent a wink in the twins' direction.

B's hand split three more mercenaries as the biggest figure in the room towered over him.

He was huge- his shaggy brown hair and techless armor cast a dark shadow over his figure. The twins had cut down every other bandit in the room- except their leader.

He spat onto the floor, a nasty smile over his lips. He pointed at B.

"Oi, you with the blank stare! C'mere, I've gotta surprise fer ya."

A snarl came from B's left, and he saw his sister charge at the man twice her size. She threw her weight across the blade, sending her body hurling across the room- she was spinning with the sword!

Her boot caught a chair and she flew upwards, yelling a war cry and slamming down the blade on the man's skull.

He sat back, dazed, blood pouring down his face. For a man so big, it was almost comical to see him turn tail and run.

"No one insults my brother," she whispered under her breath.

There was silence, as there always was in the blissful moment when combat ended.

Then, "Shit, Dimi, you sure made some friends." Claude.

Edelgard interrupted whatever B or By might say in response to that. "No time for flirting, RS will be here with this commotion."

"That might've been RS," grumbled Claude. 

Dimitri just looked at the twins and nodded quietly. He stood up, testing his augmented limbs for B's mechanical work. He nodded again, this time toward B. 

"Just one moment," Claude said. He walked up to the twins. "You're talented. It's hard to find reliable people in a fight. At least the kind that haven't been bought already." He winked. "There's an offer on the table."

By spoke before B could. "If people hunt you down in a bar, maybe this isn't the kind of work we're interested." 

Claude laughed. "Pardon me, but I know a lie when I hear one. No one does that kind of stunt you pulled unless they have experience. The offer remains open."

"We'll consider it," she said, shooting a glare at B who tried again to speak. With that quick glance they reached an understanding, a compromise. "If we wanted to, where would we find you?"

"A bar on Central Ave," Dimitri piped up, almost smiling. "It's called the Rez-pite. Bartender can put you in touch with us."

"Boys, we're on the clock," Edelgard hissed. "You wanna stay here for RS to get here, be my guest, but I'm gone." Dimitri nodded, following her lead to the door.

"Don't miss us too much!" Claude called before slipping out behind them.

Things got quiet for a moment before By and B both spoke at the same time.

"We don't know what they want-"

"They offered us work-"

A pause, a half-smirk from each of them.

"You two alright?" Jeralt asked, walking up. The people he'd been helping kept a wide berth from the three.

They nodded and Jeralt smiled.

"Good, now let's get the hell out of here."

<>

They'd found an alleyway to keep themselves dry for the night. It was smelly and wet, but never the less, it was shelter all the same. 

B sighed and released a buckle on his sister's coat, and she let out a soft breath as her armor fell heavily against the wet stone. By brushed her pants, and clouds of dust flew off them as she sat down next to her brother. 

He didn't meet her eye, just only fidgeted with a loose piece on his boot. 

"You know we can't go, right?" 

When she didn't answer, he kept speaking. 

"We've got it good, By. We're good fighters and we can't cast all that aside to go fight with some random kids we met inside a raid." 

"I know that, B. But- maybe it's a chance to make decent money and a name for ourselves?" 

"By, love, we don't even know who these people are." 

A pause. 

B nearly smirked, then caught his sister's eye. 

"I'm not that bad at speaking, y'know. You didn't have to interrupt me to keep my mouth from opening." 

That made her laugh, ever so slightly, and the day was won for him. 

<>

B turned, restless, in his sleep. Awareness flared at the back of his mind- someone was pointing a gun at him...? 

An echoing low resounded in his ears; pain exploded at the back of his skull and sirens blared in his ears- something was embedded in his brain, something sharp and metallic- the iron taste of his own blood in his mouth only made it worse, oh skies, the pain was too terrible to imagine- 

He snapped awake, sweat and tears flooding his eyes as his hands desperately ran over a scar many years since healed over. His hair was wet with rainwater and his own sweat, his shirt drenched at the front. By slept soundly beside him. 

Pleading to gods he'd never prayed to before, he nudged his sister awake. 

"Whazz goin on?" 

"By," B started, hearing the quivering in his voice as he struggled to unstick his tongue from the roof of his mouth. 

By sat up, rubbing her eyes and blearily looking up. She cupped her brother's face, thumbing away the tears he struggled to not let fall. 

"You remembered it again, didn't you?" She said softly, prompting a nod from him. 

By shook her head softly, and she opened the blankets of her sleeping bag to let him in. He pressed himself against her, and she was silently grateful for the extra heat. Her head rested between his neck and shoulder, and his arms snaked around her back. She could feel his breathing on her hair. 

They slept soundly. 

**Notes for the Chapter:**

> Sorry about the short chapter, luvs! Jess disappeared on my and I had to finish it on my own time. I'm gonna start the next chapter and probs write it on my own, I hope to hear all y'all have to say!
> 
> Happy holidays!
> 
> -FIN

**Author's Note:**

> Hope you all enjoyed our little AU fic; there will be more soon, I can promise that. Keep an eye out for updates, and both of us welcome any comments, kudos and hit we can receive.
> 
> Have a great day!
> 
> -Fin & Jess


End file.
